The present invention is related to material handling vehicles, and more particularly to a method and apparatus to reinforce the training provided to an operator of a material handling vehicle to maintain a proper position in an operator compartment while driving the vehicle.
Employers are required by OSHA standards (29 C.F.R. 1910.178(1)) to train operators of material handling vehicles in safe operation of the vehicle. The training includes instructing the operator to maintain his or her feet and legs inside of the vehicle compartment while operating the vehicle. These regulations also require the employer to prohibit operators from placing their legs outside the running lines of the vehicle.
Electromechanical and photoelectrical systems are available for producing an alarm or alert signal when an object extends into or out of the operator compartment of the vehicle while the vehicle is in use, and therefore to provide an indicator when a leg or foot is extended out of the vehicle.
One example of an electromechanical system for monitoring an operator in a material handling vehicle is disclosed, for example, in U.S. Pat. No. 6,137,398 to Dunlap. Here, an electromechanical actuator is provided across the entrance to an operator compartment. An alert signal is generated when a portion of the operator's body engages the actuator, alerting the operator when a portion of the operator's body is extending outside of the operator compartment.
A photoelectric system is disclosed in U.S. Pat. No. 4,840,248 to Silverman. Here, a photoelectric light source and corresponding detector are positioned across the entrance to an operator cab, and are activated whenever power is applied to the vehicle. When an object extends into or out of the cab of the vehicle, the beam between the source and the detector is broken, and an alarm is generated. The alarm can be a visual or audio signal to the operator, or power can be cut off to the vehicle to force the vehicle to stop. The alarm is activated whenever the operator leaves the compartment and is also used to brake the vehicle when the operator exits.
These prior art systems, however, suffer from disadvantages which make them unsuitable for either training or reinforcing the training of an operator. Both the electromechanical and photoelectric prior art systems, for example, activate the sensors whenever power is applied to the vehicle. An alarm is generated, therefore, not only when an actual fault condition has been detected, but also whenever the operator intentionally enters or leaves the vehicle. Therefore, alarm conditions are not consistently tied to actual “fault” conditions, but rather are frequently encountered in normal operation. After a period of time, therefore, operators may become immune to signals produced by these systems, and begin to ignore actual fault conditions. These devices, therefore, have limited usefulness in training or reinforce the training of operators to properly maintain a position within the vehicle.
There remains a need, therefore, for a system capable of providing alarm and alert signals to an operator which are useful in reinforcing training to maintain the feet and legs inside of the vehicle while in use.